Dynomax Bullet Mufflers

[TTAFB_SVT]

I am ordering the dynomax bullet mufflers for my GT and I need some help on which size I need. I think I need the 2.5" ones since I think that's the exhaust size of the new gt's but do i need the 4 or 5 inch model with either 16 1/2 or 23 1/2 inch diameter? Anybody know?

 

[nicetry]

get the smaller ones, mustangs do not have a lot of space for
mufflers